Mitsubishi Electronics MR-J2S- CL Manual home position return types, Length of the proximity dog

4. OPERATION

4.4Manual home position return mode 4.4.1 Outline of home position return

Home position return is performed to match the command coordinates with the machine coordinates. In the incremental system, home position return is required every time input power is switched on. In the absolute position detection system, once home position return is done at the time of installation, the current position is retained if power is switched off. Hence, home position return is not required when power is switched on again.

This servo amplifier has the home position return methods given in this section. Choose the most appropriate method for your machine structure and application.

This servo amplifier has the home position return automatic return function which executes home position return by making an automatic return to a proper position if the machine has stopped beyond or at the proximity dog. Manual motion by jog operation or the like is not required.

(1) Manual home position return types

Choose the optimum home position return according to the machine type, etc.

Type	Home position return method	Features
		General home position return method using a
	With deceleration started at the front end of a	proximity dog.
	proximity dog, the position where the first	Repeatability of home position return is
Dog type home position	Z-phase signal is given past the rear end of the dog	excellent.
return	or a motion has been made over the home position	The machine is less burdened.
	shift distance starting from the Z-phase signal is	Used when the width of the proximity dog
	defined as a home position.(Note)	can be set greater than the deceleration
		distance of the servo motor.
	With deceleration started at the front end of a	Home position return method using a
	proximity dog, the position where the first Z-phase	proximity dog.
Count type home	signal is given after advancement over the preset	Used when it is desired to minimize the
	moving distance after the proximity dog or a motion	length of the proximity dog.
position return
	has been made over the home position shift distance
	starting from the Z-phase signal is defined as a
	home position.
Data setting type home	The position reached after any automatic motion is	No proximity dog required.
position return	defined as a home position.
	The position where the machine stops when its part	Since the machine part collides with the
Stopper type home		machine be fully lowered.
	is pressed against a machine stopper is defined as a
position return		The machine and stopper strength must be
	home position.
		increased.
Home position ignorance	The position where servo is switched on is defined as
(Servo-on position as	a home position.
home position)
	The position where the axis, which had started	The Z-phase signal is not needed.
Dog type rear end	decelerating at the front end of a proximity dog, has
	moved the after-proximity dog moving distance and
reference
	home position shift distance after it passed the rear
	end is defined as a home position.
	The position where the axis, which had started	The Z-phase signal is not needed.
Count type front end	decelerating at the front end of a proximity dog, has
	moved the after-proximity dog moving distance and
reference
	home position shift distance is defined as a home
	position.
	The position where the first Z-phase signal is issued
Dog cradle type	after detection of the proximity dog front end is
	defined as a home position.

Note: The Z-phase signal is a signal recognized in the servo amplifier once per servo motor revolution and cannot be used as an output signal.

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